Automated, air-operated bellows pumps for groundwater sampling and other applications

Abstract

An air-operated pump for groundwater sampling features a corrugated bellows as opposed to the traditional bladder used for fluid collection. The preferred embodiment includes an air-supply line and a fluid-discharge line, each coupled to the pump body through a controller disposed at an appropriate above-ground location. The bellows is operable between a refill state, wherein fluid is drawn into the pump body through the fluid inlet, and a discharge state wherein fluid is forced out of the pump body through the discharge line. An apparatus disposed within the pump body governs the air received through the air-supply line to, at least, semi-automatically cycling the bellows between the refill and the discharge states. To assist in cycling, the pump may further include one or more magnets for latching the bellows in the refill or discharge state, and an electrical sensor for detecting whether or not the bellows is latched. As an alternative, the apparatus for governing the air received through the air-supply line may include a valve in the air-supply line which is mechanically coupled to the bellows. A separate exhaust line may also be provided to expel air received through the air-supply line, in which case the apparatus for governing the air received through the air-supply line also governs the air expelled through the exhaust line.

Having described my invention, I now claim:  
     
       1. An air-operated pump for groundwater sampling and other applications, comprising: 
       a submersible pump body having a fluid inlet;  
       an air-supply line and a fluid-discharge line, each coupled to the pump body from an above-ground location;  
       a corrugated bellows disposed within the pump body, the bellows having a closed end and an open end, the bellows being operable between a refill state, wherein fluid which surrounds the pump body when submerged is drawn into the pump body through the fluid inlet, and a discharge state wherein fluid is forced out of the pump body to the above-ground location through the discharge line; and  
       apparatus disposed within the pump body and coupled to the closed end of the bellows for governing the air received through the air-supply line, thereby cycling the pump between the refill and discharge states.  
     
     
       2. The pump of claim  1 , wherein the bellows is compressed during the refill state and expanded during the discharge state. 
     
     
       3. The pump of claim  1 , wherein the open end of the bellows is oriented upwardly when the pump is submersed. 
     
     
       4. The pump of claim  1 , wherein the apparatus disposed within the pump body for governing the air received through the air-supply line includes one or more magnets for latching the bellows in the refill or discharge state. 
     
     
       5. The pump of claim  1 , wherein the apparatus disposed within the pump body for governing the air received through the air-supply line includes an electrical sensor for detecting whether or not the bellows is latched. 
     
     
       6. The pump of claim  5 , further including a valve in the air-supply line which is mechanically coupled to the bellows. 
     
     
       7. The pump of claim  1 , further including a separate exhaust line to expel air received through the air-supply line. 
     
     
       8. The pump of claim  7 , wherein the apparatus disposed within the pump body for governing the air received through the air-supply line also governs the air expelled through the exhaust line. 
     
     
       9. An air-operated pump for groundwater sampling and other applications, comprising: 
       a submersible pump body having a fluid inlet;  
       an air-supply line, an exhaust line, and a fluid-discharge line, each line being coupled to the pump body from an above-ground location;  
       a corrugated bellows disposed within the pump body, the bellows having a closed end and an open end, the bellows being operable between a refill state, wherein fluid which surrounds the pump body when submerged is drawn into the pump body through the fluid inlet, and a discharge state, wherein fluid is forced out of the pump body through the discharge line; and  
       a valve assembly mechanically coupled to the bellows within the pump body, the valve assembly being operative to automatically cycle the pump given a uniform pressurization through the air-supply line by performing the following functions:  
       a) closing the air-supply line and opening the exhaust line in conjunction with the refill mode, and  
       b) opening the air-supply line and closing the exhaust line in conjunction with the discharge mode.  
     
     
       10. The pump of claim  9 , wherein the bellows is compressed during the refill state and expanded during the discharge state. 
     
     
       11. The pump of claim  9 , wherein the open end of the bellows is oriented upwardly when the pump is submersed. 
     
     
       12. The pump of claim  9 , further including one or more magnets for latching the bellows in the refill or discharge state.